Despite Celtic’s Europa League progress only beating Rangers will put lid on discontent over Champions League eliminationThat Celtic had already begun their journey home from Stockholm by the time Steven Gerrard cavorted along the Ibrox touchline in celebration of a late winner on Thursday evening felt altogether appropriate. Or, at least, the maintaining of a theme. Celtic’s comprehensive dismissal of the Swedish champions, AIK, was in contrast to Rangers’ edging past Legia Warsaw, but only one ending brought manic celebration.For Celtic, the group phase of the Europa League has felt like an alliance with a poor relation after CFR Cluj ended their Champions League dream. Twelve months ago, AEK Athens did likewise to the Scottish champions; at that stage, Brendan Rodgers had credit in the bank. This time, Neil Lennon found himself engulfed in a storm of discord that will only be removed – ludicrous though this is – with victory at Ibrox in the season’s first Old Firm game on Sunday.